1. Field of the Invention
The present invention relates to an intubation assistance apparatus for use in inserting a distal end of an intubation tube to be connected to a respirator into a target site such as a trachea of a patient.
2. Description of the Prior Art
It is sometimes necessary to practice artificial respiration, as a first-aid lifesaving treatment for a patient who is suffering from unconsciousness caused by an accident or the like. Although the artificial respiration may be practiced without having to use any instrument or apparatus, it is often the case that a respirator is used for that purpose.
In the event that a respirator is utilized to conduct artificial respiration, an intubation tube whose proximal end is connected to the respirator is inserted into the trachea of a patient to supply air to the trachea from the respirator via the tube.
In the meantime, if a patient loses consciousness, the root of a tongue is retracted to thereby block up a respiratory tract (air passage) because of the relaxation of muscles of the pharynx and the larynx and/or the gravity-caused loosening of a lower jaw.
Therefore, in the case where the afore-mentioned intubation tube is to be inserted into the trachea or a target site, it is essential to first open the blocked respiratory tract and secure an air passage by pulling up the tongue.
As an instrument for use in securing the air passage, there is known an intubation assistance instrument which is called an oral airway (see, e.g., US-A 2005-0150500).
Such an intubation assistance instrument includes an insertion section to be inserted into the trachea or its vicinity of a patient, and a guide portion (guide groove) provided in the insertion section for leading an intubation tube to the trachea of the patient when the intubation tube is inserted into the trachea of the patient. The intubation assistance instrument is inserted through the mouth of a patient who has lost consciousness, and an appropriate portion on the side of the distal end comes into contact with and lifts up a tongue root portion of the patient, thus securing the air passage.
As described in the above-mentioned prior art, the oral airway (intubation assistance instrument) is normally used in a state that the proximal end of the intubation assistance instrument is coupled to a main body of an intubation assistance apparatus (hereinafter, this state will be referred to as “coupling state”). The intubation assistance apparatus includes an image taking means (image pick-up device) for taking an image of an observation site at a distal end portion of the intubation assistance instrument as an electronic image, and a display for displaying the electronic image taken by the image taking means.
Further, in the intubation assistance apparatus of the above-mentioned prior art, there is formed an internal bore in which an image guide is inserted. The internal bore is formed so as to be substantially parallel with the guide groove.
When the intubation assistance apparatus is used in a state shown in FIG. 1 of the above-mentioned prior art, that is, when the apparatus is used in a state that the center of the screen of the display is aligned with the center of the entrance of the trachea of a patient displayed on the screen, the intubation tube is advanced toward a direction dislocated from the entrance of the trachea of the patient when the intubation is pushed forward from the distal end portion of the insertion section of the intubation assistance instrument.
Since there is a problem as described above, that is, the intubation tube is advanced toward a direction dislocated from the entrance of the trachea of the patient, the operator has to operate the intubation assistance instrument so that the intubation tube is correctly advanced toward the entrance of the trachea of the patient. This results in a problem in that the manipulability of the intubation assistance apparatus when the intubation tube is inserted into a target site of a patient is lowered.